I am a Mexican-American that just moved to Buenos Aires. Even though i knew Spanish (i was born and raised in México and then I moved to California) i must confess that the spanish here is quite different to the one Mexicans speak. It is for this reason that i would like to recommend you a show that my roommate told me about and that has made things easier for me: BAcast!!!!! They talk about different stuff… think current affairs, Argentine/American culture, philosophical issues… and the list goes on.
They also have a section called "Porteño in use¨ and ¨Spanish playground¨ in which they teach listeners words/phrases Argentines use. But do you know what is the best part, at least in my opinion???? THIS IS A BILINGUAL SHOW. One host is an American, while the other one is an Argentine so they always offer the listeners different points of view while speaking in English and Spanish! :)
If you would like to learn/practice your spanish or "castellano" (how they call it here), i will definitely recommend this show! I am sure you will find it as useful as i have!